CAIC: Colorado Avalanche Information Center

2023/01/09 - Nevada - Mummy Mountain, Spring Mountain National Recreation Area

Published 2023/03/14 by Joe Soccio, Bridgeport Avalanche Center - Simon Trautman, National Avalanche Center

Avalanche Details

  • Location: Mummy Mountain, Spring Mountain National Recreation Area
  • State: Nevada
  • Date: 2023/01/09
  • Time: 12:30 PM (Estimated)
  • Summary Description: 1 backcountry snowboarder, caught, partially buried-critical, and killed
  • Primary Activity: Backcountry Tourer
  • Primary Travel Mode: Snowboard
  • Location Setting: Backcountry


  • Caught: 1
  • Partially Buried, Non-Critical: 0
  • Partially Buried, Critical: 1
  • Fully Buried: 0
  • Injured: 0
  • Killed: 1


  • Type: SS
  • Trigger: AR - Snowboarder
  • Trigger (subcode): u - An unintentional release
  • Size - Relative to Path: R2
  • Size - Destructive Force: D2
  • Sliding Surface: I - New/Old Interface


  • Slope Aspect: S
  • Site Elevation: 10500 ft
  • Slope Angle: 37 °
  • Slope Characteristic: Gully/Couloir

Avalanche Comments

The avalanche occurred at approximately 11300 feet in a northeast-facing couloir on Mummy Mountain, which is located within the Spring Mountains National Recreation Area (Figure 1). The ski descent is locally known as Mummichog couloir. The avalanche was a soft slab triggered in new wind-deposited snow (SS-ARu-R2-D2-I). It was unintentionally triggered by a snowboarder descending the lower half of the couloir and was large enough to sweep the victim off his feet and into the trees at the base of the chute (Figure 2). In addition, several very large natural avalanches released in adjacent paths in the days following the accident. 

Backcountry Avalanche Forecast

There is no public backcountry avalanche forecast for the area.

Weather Summary

The Lee Canyon SNOTEL Site (which is approximately 1.8 miles West and 2,400 feet below the accident site) is the closest mountain weather station to the accident site. Based on information obtained from the SNOTEL, there was an early season storm in November, a period of dry conditions until mid-December, and then a series of intermittent storms that delivered ~3 inches of Snow Water Equivalent (SWE) between December 11th and Jan 8th (Figure 3).

On January 9th, the site recorded 4 inches of new snow and .6 inches of SWE.  Winds were moderate and steady from the south with gusts up to 22mph (ridgetop winds were likely much stronger). Witnesses describe overcast skies, temperatures in the low 30’s, and intermittent precipitation and blowing snow.

Snowpack Summary

The seasonal snowpack began to accumulate in early November, but the area went more than a month with no precipitation and the snowpack was very thin moving into December. December storms added depth and by January 2023 the mid-elevation snowpack was around a meter deep. Storm systems in the 1st week of January likely buried faceted snow that would serve as a weak layer for the January 9-10 avalanche cycle (Figures 4 and 5).  New snow totals from January 9-11, 2023 were approximately 1.5 - 2 feet.

Events Leading to the Avalanche

Five people left the Deer Creek Trailhead on the morning of January 9th at approximately 0800. The group was composed of both skiers and splitboarders. The objective for the day was to ascend a NE couloir on Mummy Peak (Mummichog) and descend the technical SW face (Figure 6). They scouted the route the day prior, and the group discussed ways to avoid instability within the snowpack, the need to move quickly before a forecasted afternoon/evening storm system arrived, and the technical skiing challenges for the descent on the SW face.  

As previously mentioned, a strong winter storm was forecasted to impact the area by mid to late in the day on January 9th, 2023. First-hand accounts suggest that the storm arrived earlier than the group expected and that it was in full swing by the time they reached the alpine. As the group moved up and into the couloir, they noted shallow wind slabs and active (if intermittent, cross-loading) higher in the terrain.  They dug a snowpit (Figure 7) and started a dialog on their ability to safely climb the couloir. At this point, they made a group decision to proceed with a very low threshold for turning around if the depth of the slab increased, or if the slab was found to be contiguous within the couloir.

The group order and level of snow and avalanche experience are as follows:   

Skier 1: 5+ Years of backcountry experience. AIARE Level 1. 

Skier 2: 5+ Years of backcountry experience. AIARE Level 1.

Skier 3: 15+ Years of backcountry experience. AIARE Level 2. Professional Ski Patrol. Professional Mountain Guide.

Skier 4: 2-3 Years of backcountry experience. No formal avalanche education.

Skier 5: 2-3 Years of backcountry experience. No formal avalanche education. 

Although skier 3 initially led the boot pack up the couloir he was passed by Skiers 1 and 2 after about 100 vertical feet. As the team continued up, the snow surface became more wind affected and they began to encounter thin slabs and drifts. Skier 3 told the group that the wind slab problem was present and that the slab was increasing in depth (~30cm). Skiers 1 and 2 were ~50 vertical feet above and reported that they were not seeing a significant problem and continued upward. Skier 3 continued up another 15 ft and noted the slab depth had increased to 40-50 cm. He isolated a quick column and reported a failing test. At this point, Skier 3 decided it was no longer safe to continue and suggested they should return down the bootpack. 

Skiers 1 and 2 wanted the rest of the team to ascend to a higher safe zone to continue the discussion. Skier 3 did not feel that it was safe to follow their boot pack any higher or to ski the slope. After some discussion, Skiers 3, 4, and 5 descended the bootpack to a safe zone behind a rock wall at the base of the skiers left side of the couloir. At this time, snowfall and wind transport began to increase.

Accident Summary

Although Skiers 1 and 2 agreed that they would descend, they felt the slope was safe to ski from their high point about halfway up the couloir. Reportedly, at this point Skier 2 told Skier 1 that he would have continued to the top if solo that day. Skier 1 led the descent, made ~6 turns, and stopped on a ramp behind a tree on the skiers left side of the couloir (Figure 8). At this point, no major sluffs or movement were observed within the surficial snow. Skier 2 then descended, moving past Skier 1 towards the exit of the couloir. Skier 1 observed a fast-moving sluff gathering behind Skier 2. Skier 1 shouted a warning but is unsure if it was heard. The sluff hit Skier 2 in the center of the couloir and knocked him off his feet. As he tumbled, multiple wind slabs and drifts released and carried him in a fast-moving avalanche out of the bottom of the couloir. Skiers 3, 4 and 5 witnessed the avalanche as it passed the base of the rock wall. 

Rescue Summary

Skier 1 attempted to descend to Skier 2 but lost a ski before exiting the couloir.  Skiers 3, 4, and 5 had their skis on when the avalanche occurred. After about a 30-second delay, Skier 3 started a transceiver search, quickly obtained a signal, but passed Skier 2 by ~ 30 feet downhill. Skier 4 also passed Skier 2, but he could see that he was partially buried and wrapped around a small 6-inch diameter tree (Figures 9 and 10). Skier 1 rejoined the group. Skiers 1 and 5 skied to the victim and began to extricate him from the tree.  Skier 2 had no pulse and was not breathing. It had been 3-4 minutes since the avalanche. 

Skiers 3, 4, and 5 are a paramedic, a flight nurse, and a respiratory therapist. The victim’s chest was bruised, and the sternum was depressed and unsupported. The victim’s helmet was also cracked. CPR was administered for 30 minutes and although the victim had a good chest rise with rescue breaths and a palpable pulse with compressions, the victim never had a return of spontaneous circulation. The group decided to extricate the victim. An IN-REACH SOS had already been activated and the local SAR team was reached via phone call. The storm increased in intensity as the extrication began. The group built a makeshift stretcher out of rope and ski poles and were able to move the victim about 1⁄3 of the way down the mountain before it broke. At this point, they transferred the victim to Skier 4’s snowboard and secured him by his harness, rope, and various runners and carabiners. They proceeded downward for another 1⁄3 of the descent and after about 3.5 hours they encountered the LVMPDSAR. The SAR team took the lead and transferred the victim to a rescue sled. Skiers 1 and 5 descended because they did not have headlamps. Skiers 3 and 4 assisted the SAR team in continuing extrication. The team arrived back at the Deer Creek trailhead at around 6 pm.


All the fatal avalanche accidents we investigate are tragic events. We do our best to describe each accident to help the people involved and to help the community better understand the accident. We do not intend to place any blame on the involved parties. Instead, we offer the following comments in the hope that they will help people avoid future avalanche accidents. 

The January 9, 2023 storm arrived earlier than forecast and new snow and moderate gusty winds caused new drifts and slabs to form quickly in the alpine. As a result, the avalanche hazard increased dramatically. The group knew the storm was coming but based on the timing of the weather forecast they thought they could achieve their objective before the visibility decreased and the avalanche hazard increased. 

Unfortunately, the arrival of the storm and the increase in avalanche hazard corresponded with the group’s arrival at the couloir. Although they seem to have recognized this, they made the fateful decision to move further into the terrain. 

The decision to move into the couloir increased the avalanche risk significantly and revealed fundamental differences in avalanche expertise and risk tolerance between group members. Although the group was looking at the same snowpack and traveling through the same terrain, they had differing opinions on the hazard, the amount of risk, and the path forward.

What can we learn? 

1. During storms, the avalanche hazard in alpine terrain can change on the order of minutes. Attempting big, or consequential objectives with rapidly approaching weather is a consequential decision. 

2. Even small avalanches are incredibly dangerous in steep, confined terrain where you can get swept into rocks, trees, or other obstacles.  Because of this, actively drifting couloirs can be very bad places to be. 

3. Group dynamics matter. Managing a group of 5 in confined and consequential terrain (such as a couloir) is difficult under any circumstance. In this case, even though the group recognized the hazard, differing opinions may have prolonged the decision to turn around and led to a fatal approach to managing the hazard.

4. This group performed exceptionally well during the rescue and recovery. Managing severe trauma in a field setting is difficult. Moving non-ambulatory patients through backcountry terrain is even more so. In this case, the team was able to fabricate two impromptu stretchers/sleds onsite and move the victim out of avalanche terrain before SAR arrived. This effort simplified the SAR response and significantly reduced the avalanche risk to rescuers as the storm led to a significant natural avalanche cycle the following day (Figures 11 and 12). 

Our condolences go out to the friends and family of the victim. Many thanks to skiers 1, 3, 4, and 5 for thoroughly documenting the accident and graciously sharing their experience and knowledge of the area. We also greatly appreciate the willingness of LVMPDSAR officers and volunteers to help with this report. 


Joe Soccio

Lead Avalanche Specialist

Bridgeport Avalanche Center

Humboldt-Toiyabe National Forest



Simon Trautman

Acting Director

National Avalanche Center